Stabilized hydrocarbon liquids



Patented May 20, 1952 2,597,205 a STABILIZED HYDROCABBON LIQUIDS Theodore B. Tom, Hammond, Ind., assignor to Standard Oil Company,

ration of Indiana- Chicago, III., a corpo- No Drawing. Application December 22, 1949,,

Serial No. 134,589

This invention pertains to improved light hydrocarbon oils andmore particularly relates to light petroleum distillates in which the corrosiveness of the contained sulfur compounds is inhibited.

It is well known that hydrocarbon oils, particularly light hydrocarbon distillates, such as petroleum distillates, usually marketed as fuel oils, motor fuels, solvents and the like, aresubjected to various tests to determine whether or not they pass certain specifications. One of the tests usually required is the so-called copper staining or copper corrosion test in which a highly polished copper strip is immersed in the hydrocarbon liquid under specified conditions to determine whether or not the hydrocarbon distillate will cause ablackening or discoloration of the copper strip. The primary purpose of this 4 Claims. (CI. 44-50) num. While the hydrophilic colloid can be used as such, I prefer to use the oil-soluble portions of such materials. The oil-soluble portion can be obtained by extracting the hydrophilic colloid with a suitable solvent, such as for example, benzene, toluene, xylene, isopropanol, ethyl acetate,

. -etc., and subsequently removing the solvent from test is to detect the presence of corrosive sulfur. I

It is, therefore, highly desirable to inhibit the corrosiveness of sulfur in such distillates.

It is an object of the present invention to provide a hydrocarbon oil which will pass the copper strip test. Another object of the invention is to provide a hydrocarbon distillate in which the corrosiveness of the sulfur compounds contained therein is inhibited. Still another object of the invention is to provide an improved distillates, to cause discoloration of copper in contact with such distillates due to the presence.

of active sulfur contained therein can be substantially inhibited by incorporating in such distillates from about 0.005% to about 1.0%, and preferably from about 0.01% to about 0.1% of the oil-soluble portion of an organic hydrophilic colloid of the type usually used for preventing the deposition of boiler scale. Examples of suit able hydrophilic colloids are seaweed extracts, tannin, gelatin, olibanum, etc. A hydrophilic colloid particularly well adapted for this purpose is "Sand-Banum which is a suspension of natural resins composed particularly of olibapared with standard copper strips for visual rat- 7 the extract.

Alternatively, the hydrocarbon distillate can be mixed with the hydrophilic colloid, such as for example, olibanum, to extract the oil-soluble constituents therefrom followed by the separation of the oil-insoluble material from the hydrocarbon distillate containing dissolved therein the'oil-soluble constituent of the hydrophilic colloid.

The effectiveness of a small amount of a hydrophilic colloid in hydrocarbon distillates in .inhibiting copper staining due to corrosive sulfur is demonstrated by the data. in the following table. The tendency of sulfur compounds in petroleum distillates to stain copper is best determined by the copper strip corrosion test. This test is carried out by placing a clean strip of polished, pure copper in a clean six inch test tube and adding a suflicient amount of the sample to be tested to completely cover the strip]. .The test tube is closed with, a vented stopper and placed in an upright position in an appropriate bath maintained at the specified temperature, and at the end of a specified test period the strip is removed from the test tube, dried and comings expressed as corrosion number. A corrosion number of 12 denotes ascaly black strip indicative of a very corrosive sample, while a corrosion number of 0 denotes an-unstained strip which is indicative-of a non corrosive stock. Strips having varying degrees of staining are given intermediate numerical corrosion number ratings. A corrosion number higher than 7 is not satisfactory and for most special naphthas a corrosion number of 5 or less is required. A description of the copper strip tests and the determination of corrosion number ratings can be found in the article by. J. A. Bolt entitled "Copper-Strip Corrosion Tests, published in the Oil and Gas Journal August 9,1947. Depending on the specification for a particular distillate, the duration of the test varies and may be for as short as ten minutes and as long as twenty-four hours. Likewise, the temperature at which the test is made varies depending upon the specification from 122 F. to the initial boiling point of the distillate being tested. The results tabulated in 3 I Table I were obtained by immersing freshly polished copper strips in samples of boiling petroleum distillates for a period of thirty minutes. These distillates, having initial boiling points of about 300 F. and maximum boiling points of from about 418 F. to about 430 F. contained varying amounts of the inhibitor.

1 Oil-soluble fraction of Sand-Barium.

Although in the above experiments the hy drophilic colloid material was addedto the distillate as an additive, equally eifective results are obtained by contacting the hydrocarbon oil and the colloid in any convenient manner, for example by agitating the two materials together and separating the oil-soluble from the-oil-insoluble substance.

The term sulfur compounds" as used herein and in the appended claims includes elemental sulfur, hydrogen sulfide, and corrosive organic sulfur compounds.

While I have described my invention by reference to specific embodiment thereof, the invention is not limited by the same, but includes within its scope such modifications as come within the spirit of the appended claims.

I claim:

1. A composition consisting essentially of a hydrocarbon oil distillate, containing a sulfur compound corrosive to copper as a constituent thereof, and from about 0.005% to about 1%, by weight, of the oil-soluble fraction of olibanum.

2. A composition as described in claim 1 in which the hydrocarbon oil-distillate is a petroleum oil distillate.

3. A composition as described in claim 1 in which the hydrocarbon oil distillate is a fuel oil. 4. A composition as described in claim 1 in which the hydrocarbon oil distillate ,is a motor fuel.

THEODORE B. TOM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Date Scherer Aug. 14, 1945 

1. A COMPOSITION CONSISTING ESSENTIALLY OF A HYDROCARBON OIL DISTILLATE, CONTAINING A SULFUR COMPOUND CORROSIVE TO COPPER AS A CONSTITUENT THEREOF, AND FROM ABOUT 0.005% TO ABOUT 1%, BY WEIGHT, OF THE OIL-SOLUBLE FRACTION OF OLIBANUM. 